linux/drivers/crypto/nx/nx-aes-ctr.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * AES CTR routines supporting the Power 7+ Nest Accelerators driver
   4 *
   5 * Copyright (C) 2011-2012 International Business Machines Inc.
   6 *
   7 * Author: Kent Yoder <yoder1@us.ibm.com>
   8 */
   9
  10#include <crypto/aes.h>
  11#include <crypto/ctr.h>
  12#include <crypto/algapi.h>
  13#include <linux/module.h>
  14#include <linux/types.h>
  15#include <linux/crypto.h>
  16#include <asm/vio.h>
  17
  18#include "nx_csbcpb.h"
  19#include "nx.h"
  20
  21
  22static int ctr_aes_nx_set_key(struct crypto_skcipher *tfm,
  23                              const u8               *in_key,
  24                              unsigned int            key_len)
  25{
  26        struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
  27        struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
  28
  29        nx_ctx_init(nx_ctx, HCOP_FC_AES);
  30
  31        switch (key_len) {
  32        case AES_KEYSIZE_128:
  33                NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_128);
  34                nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_128];
  35                break;
  36        case AES_KEYSIZE_192:
  37                NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_192);
  38                nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_192];
  39                break;
  40        case AES_KEYSIZE_256:
  41                NX_CPB_SET_KEY_SIZE(csbcpb, NX_KS_AES_256);
  42                nx_ctx->ap = &nx_ctx->props[NX_PROPS_AES_256];
  43                break;
  44        default:
  45                return -EINVAL;
  46        }
  47
  48        csbcpb->cpb.hdr.mode = NX_MODE_AES_CTR;
  49        memcpy(csbcpb->cpb.aes_ctr.key, in_key, key_len);
  50
  51        return 0;
  52}
  53
  54static int ctr3686_aes_nx_set_key(struct crypto_skcipher *tfm,
  55                                  const u8               *in_key,
  56                                  unsigned int            key_len)
  57{
  58        struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
  59
  60        if (key_len < CTR_RFC3686_NONCE_SIZE)
  61                return -EINVAL;
  62
  63        memcpy(nx_ctx->priv.ctr.nonce,
  64               in_key + key_len - CTR_RFC3686_NONCE_SIZE,
  65               CTR_RFC3686_NONCE_SIZE);
  66
  67        key_len -= CTR_RFC3686_NONCE_SIZE;
  68
  69        return ctr_aes_nx_set_key(tfm, in_key, key_len);
  70}
  71
  72static int ctr_aes_nx_crypt(struct skcipher_request *req, u8 *iv)
  73{
  74        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
  75        struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
  76        struct nx_csbcpb *csbcpb = nx_ctx->csbcpb;
  77        unsigned long irq_flags;
  78        unsigned int processed = 0, to_process;
  79        int rc;
  80
  81        spin_lock_irqsave(&nx_ctx->lock, irq_flags);
  82
  83        do {
  84                to_process = req->cryptlen - processed;
  85
  86                rc = nx_build_sg_lists(nx_ctx, iv, req->dst, req->src,
  87                                       &to_process, processed,
  88                                       csbcpb->cpb.aes_ctr.iv);
  89                if (rc)
  90                        goto out;
  91
  92                if (!nx_ctx->op.inlen || !nx_ctx->op.outlen) {
  93                        rc = -EINVAL;
  94                        goto out;
  95                }
  96
  97                rc = nx_hcall_sync(nx_ctx, &nx_ctx->op,
  98                                   req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
  99                if (rc)
 100                        goto out;
 101
 102                memcpy(iv, csbcpb->cpb.aes_cbc.cv, AES_BLOCK_SIZE);
 103
 104                atomic_inc(&(nx_ctx->stats->aes_ops));
 105                atomic64_add(csbcpb->csb.processed_byte_count,
 106                             &(nx_ctx->stats->aes_bytes));
 107
 108                processed += to_process;
 109        } while (processed < req->cryptlen);
 110out:
 111        spin_unlock_irqrestore(&nx_ctx->lock, irq_flags);
 112        return rc;
 113}
 114
 115static int ctr3686_aes_nx_crypt(struct skcipher_request *req)
 116{
 117        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 118        struct nx_crypto_ctx *nx_ctx = crypto_skcipher_ctx(tfm);
 119        u8 iv[16];
 120
 121        memcpy(iv, nx_ctx->priv.ctr.nonce, CTR_RFC3686_NONCE_SIZE);
 122        memcpy(iv + CTR_RFC3686_NONCE_SIZE, req->iv, CTR_RFC3686_IV_SIZE);
 123        iv[12] = iv[13] = iv[14] = 0;
 124        iv[15] = 1;
 125
 126        return ctr_aes_nx_crypt(req, iv);
 127}
 128
 129struct skcipher_alg nx_ctr3686_aes_alg = {
 130        .base.cra_name          = "rfc3686(ctr(aes))",
 131        .base.cra_driver_name   = "rfc3686-ctr-aes-nx",
 132        .base.cra_priority      = 300,
 133        .base.cra_blocksize     = 1,
 134        .base.cra_ctxsize       = sizeof(struct nx_crypto_ctx),
 135        .base.cra_module        = THIS_MODULE,
 136        .init                   = nx_crypto_ctx_aes_ctr_init,
 137        .exit                   = nx_crypto_ctx_skcipher_exit,
 138        .min_keysize            = AES_MIN_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
 139        .max_keysize            = AES_MAX_KEY_SIZE + CTR_RFC3686_NONCE_SIZE,
 140        .ivsize                 = CTR_RFC3686_IV_SIZE,
 141        .setkey                 = ctr3686_aes_nx_set_key,
 142        .encrypt                = ctr3686_aes_nx_crypt,
 143        .decrypt                = ctr3686_aes_nx_crypt,
 144        .chunksize              = AES_BLOCK_SIZE,
 145};
 146